The present invention relates in general to a grommet member. More particularly, the invention relates to a grommet member that is adapted for use with corrugated metal decking and an associated electrical trench which carries electrical wiring for coupling to the metal decking cells. The grommet member of the present invention is in particular, adapted to simplify the coupling of electrical wiring as will be defined in more detail hereinafter.
Reference may now be made to the perspective view of FIG. 1 which illustrates the present technique for providing coupling passages between the metal decking 10 and an electrical trench 12. FIG. 1 also illustrates the problems that are associated with the providing of these coupling passageways. FIG. 1 also illustrates the standard grommet 14 that is employed to provide a passageway from the electrical trench 12 into a cell 16 in the metal decking. The grommet 14 is used for preventing any jagged edges associated with the metal from interfering with electrical wiring that passes into the cell 16 from the electrical trench 12.
Typically, the metal decking 10, which is of corrugated form, including crest walls 18, trough walls 20, and web 22, is provided with one or more holes such as the hole 24 illustrated in FIG. 1 in the top crest wall 18. These holes 24 are typically centrally disposed between the corresponding web sides.
The electrical trench 12 is also provided with similarly sized holes 26. These holes 26 are pre-punched. The electrical trench 12 is typically quite long and extends over a great number of corrugations of the metal decking. What occurs very typically is that the holes in the electrical trench 12 become out of registry for one reason or another with the holes in the metal decking. This may occur because of some slight mistake in punching the holes, or because of other inaccuracies, either associated with the manufacture of the product or associated with the installation thereof. In FIG. 1, at the left trough wall 18, this misalignment or misregistration is illustrated in which the underlying hole 24 in the corrugated metal decking is out-of-alignment with the hole 26 in the electrical trench 12. This problem is remedied at the present time by at least partially patching the hole 26 as illustrated by the patch 28 illustrated in phantom outline in the rightmost section of the electrical trench illustrated in FIG. 1. It is also necessary to repunch the hole 26 so that it is in proper alignment with the underlying hole 24 in the metal decking. Actually, this subsequent punching or drilling is more easily accomplished when the holes are more off-center, but in either case, where there is any misalignment, problems occur, and much time and effort has to go into correcting the matter. As indicated previously, this requires, at the very least, a patching of the improperly positioned hole 26 and then a subsequent drilling or punching operation so as to locate the hole 26 in the proper position relative to the underlying hole 24 in the corrugated metal decking. This means that additional time and expense has to be used in correcting this misalignment problem before the grommet 14 can even be used in the hole. The patching may well require the use of some type of welding equipment and when the misalignment is only slight, this may also require the use of other cutting tools other than simply a drill. This additional work is not only time consuming, but is also very labor intensive, thus significantly adding to the cost of installing decking and associated trench of this type.
Accordingly, it is an object of the present invention to overcome the aforementioned problems associated with alignment of the decking and overlying electrical trench.
A further object of the present invention is to provide an improved electrical trench grommet member that is used so as to greatly simplify the forming of a grommeted hole or passageway to enable electrical wiring coupling between an electrical trench and cells of a corrugated metal decking which is comprised of alternating crests and troughs forming such cells.